1 files changed, 29 insertions, 0 deletions
diff --git a/patches/server/0752-Oprimise-map-impl-for-tracked-players.patch b/patches/server/0752-Oprimise-map-impl-for-tracked-players.patch
new file mode 100644
index 0000000000..e1ee820045
--- /dev/null
+++ b/patches/server/0752-Oprimise-map-impl-for-tracked-players.patch
@@ -0,0 +1,29 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Spottedleaf <[email protected]>
+Date: Fri, 19 Feb 2021 22:51:52 -0800
+Subject: [PATCH] Oprimise map impl for tracked players
+
+Reference2BooleanOpenHashMap is going to have
+better lookups than HashMap.
+
+diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
+index e811c7d617b8c9cc684bc0a58a98d5ecfe11db02..f47e2d4a7343f3e3ee68f36688720cedc58861dc 100644
+--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
++++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
+@@ -110,6 +110,7 @@ import org.slf4j.Logger;
+ import org.bukkit.craftbukkit.generator.CustomChunkGenerator;
+ import org.bukkit.entity.Player;
+ // CraftBukkit end
++import it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet; // Paper
+ 
+ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider {
+ 
+@@ -2212,7 +2213,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
+         final Entity entity;
+         private final int range;
+         SectionPos lastSectionPos;
+-        public final Set<ServerPlayerConnection> seenBy = Sets.newIdentityHashSet();
++        public final Set<ServerPlayerConnection> seenBy = new ReferenceOpenHashSet<>(); // Paper - optimise map impl
+ 
+         public TrackedEntity(Entity entity, int i, int j, boolean flag) {
+             this.serverEntity = new ServerEntity(ChunkMap.this.level, entity, j, flag, this::broadcast, this.seenBy); // CraftBukkit